新建pxc001服务器： 系统：centos7 内存：2G 磁盘：128G IP地址：192.168.0.201（第一节点） 192.168.0.202 192.168.0.203
#vi /etc/selinux/config SELINUX=disabled #修改该项为disabled #执行命令 setenforce 0 #systemctl restart firewalld 开放防火墙这4个端口 firewall-cmd --add-port=4444/tcp --permanent firewall-cmd --add-port=4567/tcp --permanent firewall-cmd --add-port=4568/tcp --permanent firewall-cmd --add-port=3306/tcp --permanent
安装集群 #yum -y install http://www.percona.com/downloads/percona-release/redhat/0.1-4/percona-release-0.1-4.noarch.rpm #yum -y update percona-release #yum -y install Percona-XtraDB-Cluster-57
启动mysql，并修改密码
service mysql start
grep 'temporary password' /var/log/mysqld.log
[Note] A temporary password is generated for root@localhost: u8E;M:,p_T&H #mysql -uroot -pu8E;M:,p_T&H mysql> update mysql.user set authentication_string=password('BingoData@1024.com') where user='root' and Host = 'localhost';
使用下面方式启动第一台机器（201服务器）,这台叫引导节点。 只有这一台是这样启动。别的服务器用service mysql start启动 #ssh 192.168.0.201 #systemctl start mysql@bootstrap.service 进入mysql #mysql -uroot -pBingoData@1024.com #set wsrep_causal_reads =1; 避免各个节点的数据不一致，这种情况需要等待全同步复制 将此文件复制到master1、master2，注意要把 wsrep_node_name 和 wsrep_node_address 改成相应节点的 hostname 和 ip。
创建配置文件中对应的用户 所有节点的IP都要创建 #mysql -uroot -pBingoData@1024.com mysql> grant all privileges on . to 'pxcuser'@'%' identified by 'BingoData@1024.com'; 报错如下： ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement. 解决办法： mysql> set password = password('BingoData@1024.com'); mysql> grant all privileges on . to 'pxcuser'@'%' identified by 'BingoData@1024.com'; mysql> grant all privileges on . to 'pxcuser'@'localhost' identified by 'BingoData@1024.com'; mysql> flush privileges;
进入202和203服务器配置 #ssh 192.168.0.203 注意203和202的启动方式 #service mysql start 创建配置文件中对应的用户 所有节点的IP都要创建 mysql> grant all privileges on . to 'pxcuser'@'%' identified by 'BingoData@1024.com'; mysql> grant all privileges on . to 'pxcuser'@'localhost' identified by 'BingoData@1024.com'; mysql> flush privileges;
注意：服务的启动和停止要对应 service mysql stop ------> 启动时用service mysql start systemctl stop mysql@bootstrap.service -----> 启用是用 systemctl start mysql@bootstrap.service
注意避坑：/var/lib/mysql/grastate.dat文件中safe_to_bootstrap为1的服务器是主库,用主库的方式启动！！我们想让谁做主库也可以手动设置该服务器,而且三台集群的uuid也相同才可以启动。
seqno为-1表示已加入到集群，数据库关闭后seqno会变。 下面这台服务器201做主库启动后，seqno从4变成了-1，表示已经加入集群。
203服务器做从库一直无法启动。 启动方式是：service mysql start 报错信息如下#tail -fn 100 /var/log/mysqld.log 2020-01-10T09:25:56.982598Z 0 [Note] WSREP: (32d9017e, 'tcp://0.0.0.0:4567') turning message relay requesting off 2020-01-10T09:26:23.489499Z 0 [Note] WSREP: (32d9017e, 'tcp://0.0.0.0:4567') turning message relay requesting on, nonlive peers: tcp://192.168.0.202:4567 2020-01-10T09:26:24.489792Z 0 [Note] WSREP: (32d9017e, 'tcp://0.0.0.0:4567') reconnecting to 30d8eb06 (tcp://192.168.0.202:4567), attempt 0 2020-01-10T09:26:24.494967Z 0 [ERROR] WSREP: failed to open gcomm backend connection: 110: failed to reach primary view (pc.wait_prim_timeout): 110 (Connection timed out) at gcomm/src/pc.cpp:connect():159 2020-01-10T09:26:24.495007Z 0 [ERROR] WSREP: gcs/src/gcs_core.cpp:gcs_core_open():209: Failed to open backend connection: -110 (Connection timed out) 2020-01-10T09:26:24.495376Z 0 [ERROR] WSREP: gcs/src/gcs.cpp:gcs_open():1514: Failed to open channel 'pxc-cluster-test' at 'gcomm://192.168.0.202,192.168.0.203,192.168.0.201': -110 (Connection timed out) 2020-01-10T09:26:24.495402Z 0 [ERROR] WSREP: gcs connect failed: Connection timed out 2020-01-10T09:26:24.495415Z 0 [ERROR] WSREP: Provider/Node (gcomm://192.168.0.202,192.168.0.203,192.168.0.201) failed to establish connection with cluster (reason: 7) 2020-01-10T09:26:24.495423Z 0 [ERROR] Aborting
解决办法：把203服务器的grastate.dat文件的uuid修改的和202，201一模一样就可以启动了。 safe_to_bootstrap: 设置为0 那么UUID是什么呢？ 为什么同一个pxc集群的UUID是相同的呢？
验证集群：show status like 'wsrep%';
| wsrep_incoming_addresses | 192.168.0.202:3306,192.168.0.203:3306,192.168.0.201:3306 | | wsrep_cluster_weight | 3 | | wsrep_desync_count | 0 | | wsrep_evs_delayed | | | wsrep_evs_evict_list | | | wsrep_evs_repl_latency | 0/0/0/0/0 | | wsrep_evs_state | OPERATIONAL | | wsrep_gcomm_uuid | e9e76881-338f-11ea-90d6-3b07eeeaf3a4 | | wsrep_cluster_conf_id | 3 | | wsrep_cluster_size | 3 | | wsrep_cluster_state_uuid | 9d5bc8a5-3374-11ea-9aac-b3599f4e37e4 | | wsrep_cluster_status | Primary | | wsrep_connected | ON | | wsrep_local_bf_aborts | 0 | | wsrep_local_index | 2 | | wsrep_provider_name | Galera | | wsrep_provider_vendor | Codership Oy info@codership.com | | wsrep_provider_version | 3.41(rb3295e6) | | wsrep_ready | ON
